Picrosirius Red Polarization Staining: A Technique To Detect Fibrosis in Cardiac Tissue Sections Using Bright-Field Microscopy

After fixing the heart tissue, place it on a tissue sectioning device, cut it into 2-millimeter-thick slices, and place the sections in an embedding cassette.

Following paraffin embedding and additional sectioning according to the text protocol, deparaffinize the slides by placing them into a tank with xylene for 30 minutes. Then, rehydrate the tissue in a sequentially diluted alcohol series, followed by distilled water.

Next, use adequate picrosirius red solution to completely cover the tissue sections, and incubate for one hour. Then, use a 0.5% acetic acid solution to rinse the slides two times, and rinse the samples twice in absolute alcohol.

Air-dry the samples, and mount them in synthetic resin with a coverslip. Then, use visible light under a microscope at 200X magnification to image the slides.